Cellphone users rely on their devices for a wide range of services every day, from communication to entertainment. Indeed, the cellular infrastructure has expanded to the point that no matter where the user is, there is probably cellular service. However, sometimes the precise location of the user still matters a great deal.
More than a decade ago, cellphone users acquired the ability to determine their location on the earth's surface via GPS, and now an entire class of services uses GPS and other location technologies to enhance the user experience. This class of services, referred to as “location-based” services, includes customized search options, navigational assistance, locality-based advertisements and suggestions, and so on.
Typically, WiFi networks and GPS and are used to provide location data for location-based services. WiFi networks are typically short range, such that a device's presence on a particular WiFi network serves to roughly resolve the device's location. For greater accuracy, GPS operates by calculating a device's location relative to multiple earth-orbiting satellites.
However, since GPS satellite signals may be attenuated, it is important that a device be able to accurately and reliably capture such signals. For a single GPS antenna on a device, the GPS signal strength is impacted differently by different mechanical modes of use, e.g., free space, head and hand, hand only, etc. Moreover, for consistent performance, GPS Upper Hemisphere Isotropic Sensitivity performance specifications should be met regardless of the mechanical use mode (e.g., both left and right head and hand).
Typically, however, the location of the GPS antenna on the device is largely determinative of the device's GPS performance in various orientations and user-handling conditions. While it is possible to implement an antenna placement that balances performance between left and right side of the head, such a solution would necessarily represent a compromise with respect to performance in any given mode. Also, such an antenna placement may interfere with the placement of other antennas.
It is also possible to employ switched GPS antennas, that is, to use multiple GPS antennas and switch between these antennas based on additional input, e.g., data from an accelerometer. This technique would provide some degree of adaptability of the radiation pattern to suit different usage conditions but would not account for user loading of an antenna.
While the present disclosure is directed to a system that can eliminate some of the shortcomings noted in this Background section, it should be appreciated that any such benefit is not a limitation on the scope of the disclosed principles, or of the attached claims, except to the extent expressly noted in the claims. Additionally, the discussion of technology in this Background section is reflective of the inventors' own observations, considerations, and thoughts, and is in no way intended to accurately catalog or comprehensively summarize the prior art. As such, the inventors expressly disclaim this section as admitted or assumed prior art with respect to the discussed details. Moreover, the identification herein of a desirable course of action reflects the inventors' own observations and ideas and should not be assumed to indicate an art-recognized desirability.